Source: Wired Magazine

Vials of a potentially harmful pathogen have gone missing at Fort Detrick, the Army's main biodefense lab. But don't freak out. The samples of Venezuelan Equine Encephalitis (VEE) virus are relatively small. The Army has found "no evidence yet of criminal misconduct," the Washington Post reports. And the virus usually causes only "a mild flulike illness" -- although "brain inflammation and death" are possible, too. "It has potential for use as a biological weapon but is far less lethal than some other agents the lab works with."

And that's the real thing to keep in consideration. This isn't anthrax, it's a relatively non-lethal biological agent. Yes, it is highly infectious and easily aerosolized. Yes, that makes VEE a good candidate for military applications. And yes, as a virus, once a person is infected, there is no cure; like the flu, you have to ride out the effects. But it's not really a mass casualty tool, if you're a terrorist looking for lots of bodies. That is to say, if someone were to get a quantity of VEE agent and some cooperative mosquitoes, it would lay up a number of people in the hospital, but the virus would not kill people as aerosolized anthrax would. And because the agent is not contagious, a VEE outbreak within the United States could be rapidly contained by existing public health measures. 

This is yet another illustration of the difficulty of implementing biosecurity controls. This isn't like counting nukes or chemical munitions. Biological material can be grown, and on the other hand, it can die off. So what happens if the bugs in a few test tubes die off, and the scientist just shrugs and cleans them out without noting the action in his lab books? A few years later, and people wonder, what happened to the material in test tubes 45-48? Too late to find out, memories slip, records don't show anything. This isn't a crisis situation, but it is a tough nut to crack.

"We'll probably never know exactly what happened," one Army official tells the Post. "It could be the freezer malfunction. It could be they never existed."